What does IP mean?

What does IP mean?

IP is the abbreviation of the English Internet Protocol, which means "protocol for interconnection between networks", which is a protocol designed for computer networks to connect to each other for communication.

In the Internet, it is a set of rules that enable all computer networks connected to the Internet to communicate with each other. It stipulates the rules that computers should abide by when communicating on the Internet. Computer systems produced by any manufacturer can interconnect with the Internet as long as they comply with the IP protocol.

It is precisely because of the IP protocol that the Internet has rapidly developed into the world's largest and open computer communication network. Therefore, the IP protocol can also be called "Internet Protocol".

IP addresses are used to give computers on the Internet a number. What we see every day is that every connected PC needs an IP address in order to communicate normally. We can compare "personal computer" to "a telephone", then "IP address" is equivalent to "telephone number".

Extended information:

IP fragmentation and reorganization

Fragmentation The final IP packet cannot be reassembled until it reaches its destination. Reassembly is done by the IP layer of the destination, with the goal of making the fragmentation and reassembly process transparent to the transport layers (TCP and UDP). Packets that have been fragmented may be fragmented again (more than once).

Reason for IP fragmentation

The link layer has the feature of maximum transmission unit MTU, which limits the maximum length of the data frame. Different network types have an upper limit. The MTU of Ethernet is 1500, you can use the netstat -i command to check this value.

If the IP layer has a data packet to be transmitted, and the length of the data packet exceeds the MTU, then the IP layer will fragment the data packet so that the length of each fragment is less than or equal to the MTU. .

We assume that we want to transmit a UDP data packet. The MTU of Ethernet is 1500 bytes. Generally, the IP header is 20 bytes and the UDP header is 8 bytes. The payload part of the data is reserved. 1500-20-8=1472 bytes. If the data part is larger than 1472 bytes, fragmentation will occur.

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